Process for the production of vat dyestuffs



Patented Aug. 11, 1931 warren sraras PATENT oFFicE ARTHURLll'TTRINGHAUS, OIE IMANNHEIIYI, AND PAUL NAWIASKY AND ABTUR KB-AUSE,

OF LUDWIC-SHAFEN-GN-THE-RHINE, GERMANY, ASSIGNORS TO GENERAL ANILINEWORKS, INC., OF NEW YORK, JET. Y., A GDR-PORATIQN OF DELAWARE PROCESSFOR THE PRODUCTION OF VAT DYESTUFFS No' Drawing. Application filed July22, 1927, Serial No. 207,812, and in Germany August 17, 1926.

, thrones containing a further nucleus attached to the mesoandl-positions, at'least to the latter by means of a nitrogen atom, andhalo genated in the 2-position, in which anthrone derivatives the saidfurther nucleus may contain one or more nitrogen atoms, such forinstance as 2-halogen-anthrapyrimiclones, 2-halogen-anthrapyridones,2-halo gen-anthrapyrimidines, 2-halogen-coeramidonines and others, withmetals or agents which react similarly to metals.

It is sometimes advantageous, and when 2-halogen-pyrazolanthrones areemployed as initial materials, even essential, to employacetyl-Z-brom-pyrazolanthrone.

acyl derivatives of the said compounds for this process. :When heatingis continued for a longer time, such acyl groups are split off either inpart or completely, or, if necessary, the reaction product is finallysaponified.

The following examples will further illustrate how this invention may becarried out in practice, but the invention is not limited to theseexamples. The parts are by weight.

Example 1 1 part of acetyl-2-brom-pyrazolanthrone, melting at from 209to 211 C., which may be obtained, for example by heating2-brompyrazolanthrone with acetic anhydride and a small amount ofconcentrated sulfuric acid, is thoroughly mixed with 1 part of copperand 1 part of naphthalene, whereupon the mixture is heated to from 230to 250 C. until the condensation is complete. The reaction miXture isfreed from naphthalene and copper, according to the known methods, andthe residue recrystallized from monochlorbenzene. The acetyl compoundthus obtained consists of yellowish crystalline leaflets, which dissolvein sulfuric acid with reddish orange coloration. On pouring the sulfuricacid solution into water, a yellow dyestuff corresponding to thatobtainable by heating pyrazolanthrone with caustic alkalies, separatesout.

The initial material probably has the structure corresponding to theformula given in the followingscheme, which illustrates the probableprogress of the reaction:

00cm 00cm 00cm ll t i d ope/f0 Example 2 1 part of2-brom-anthrapyrimidonemethyl ether melting at from 285 to 290 0., whichmay be obtained, for example, by methylating 2-brom-anthrapyrimidone, is

thoroughly mixed with 1 part of copper pow- V cotton bright yellowdyeings very fast to 1 (ill chlorine and boiling with soda from thebrownish-red vat;

The initial material probably has the structure corresponding to theformula given in v i 5 the following scheme, which illustrates theprobable progress of the reaction:

2 -brom-an thrapyrimidoncmethylc their.

EwampZe. 3

1 part of 2-iodo-methyl-anthrapyrimidine melting at from 210 to 215 C.and probably having the formula givenrbelow, which may be obtained forinstance by boiling Q-diazomethyl-anthrapyrimidine with an aqueoussolution of potassium iodide, is thoroughly mixed with 1 part of copperand 2 parts of naphthalene, and this mixture is heated to 200 to 205 C.until the condensation is complete. The dyestufi? is separated accordingto the method described in Example 2. It dissolves in sulfuric acid withyellow-coloration and. dyes cotton lemon yellow shades of excellentfastness from the yellowish-brown vat.

The probable 'progress of the reaction is illustrated by the followingscheme:

in; V on; em 1 o V r a f i 2-iodo-methy1-anthrapyrimidine Example ,4

brownish-redcoloration in sulfuricnacid and dyes cotton from an orangered vat the same shade, which on exposure to the airichanges '5 to abright reddish-brown.

The probable progress of the reaction is illustrated by the followingscheme:

2-iodo-co eramidonine.

The same dyestuif is obtained, but in a somewhat less pure state, byheating 2-bromcoeramidonine melting at 210 C. with copper andnaphthalene in the manner just described.

A quite analogous, practically insoluble condensation product, of highmelting point, which dyes cotton from the vat in light yellow shades isobtained from 2 brom-anthrapyridone-inethyl ether (melting at from 255to 260 (1, and obtainable for instance by inethylating2-brom-anthrapyridone) by heating with copper and naphthalene.

1V hat we "claim' is 1. A process for the manufacture of prac ticallyinsoluble condensation products of high melting point having thecharacter of vat dyestufls which comprises heating an anthronecontaining a further nucleus at tached to the mesoand l-positions, atleast 'to the latter by means of a nitrogen atom,

and halogenated in the 2-position, with copper, care being taken that inthe case of pyra- ZOl-EllitlllOIlBS the initial material is acylated onthe nitrogen atom of the pyrazol ring.

A process for the manufacture of practically insoluble condensationproducts of high melting point having the character of vat dyestuffswhich comprises heating a 2- l1alogen-coeramidonine with copper.

3. As new articles of manufacture practically insoluble condensationproducts of high melting point having the character of vat dyestuffs,which are obtainable by heating Q-halogencoeramidonines with Copper.

4. As a new article of manufacture, a vat dyestufl which is obtainablevby heating- 2- iodo-coeramidonine with copper, dissolves withbrownish-red coloration in sulfuric acid and dyes cotton brightreddish-brown shades.

In testimony whereof we have hereunto set our hands.

ARTHUR Li'rrirnINeHAUs.v PAUL NAWIASKY.

ARTDitAiu Ub'E.

III

